Analysis Of Clinical Data In Different Electrophysiological Subtypes Of Guillain-Barre Syndrome

Background:Guillain-Barrésyndrome (GBS) is also called acute inflammatory demylinating polyneuropathy (AIDP). It is classified as AIDP, acute motor axonal neuropathy (AMAN) and acute motor-sensory axonal neuropathy (AMSAN). The clinical characteristics, electrophysiological abnormalities and prognosis between demyelinating and axonal GBS are seldom reported in China.Objective:To analyze the clinical characteristics, electrophysiological abnormalities and prognosis between demyelinating and axonal GBS.Method:(1) The 90 patients diagnosed as GBS were divided to two groups, demyelinating type (57 cases) and axonal type (33 cases). The age on onset, presymptoms, time to peak were investigated. The muscular force score and grade of sensory abnormality in nadir, cranial nerve impairment, respiratory failure and ratio of several cases were conducted. (2) The nerve conduction study (NCS) and electromyography (EMG) were conducted between 2 and 4 weeks after onset. Its distribution were studied that the distal motor latency (DML), motor conduction velocity (MCV), sensor conduction velocity (SCV), compound muscle action potential (CMAP), sensory nerve action potential (SNAP), F-wave, H reflex, spontaneous potentials, polyphase wave and motor unit recruitment. (3) Two groups was evaluated in nadir stage and 1 month, 3 month, 6 month after onset with Hughes grading. (4) Statistical analysis was conducted by SPSS 11.0 software. Measurement data was expressed in mean±SD; Independent samples T test was used to compare 2 groups of data; Rank sum test was used to compare ranked data and chi-square test was used to compare enumeration data; P values<0.05 were defined as statistical significance.Results:(1) There was no difference in age on onset, presymptoms, time to peak, muscular force score and grade of sensory abnormality in nadir, cranial nerve impairment and ratio of severe cases between the demyelinating and axonal GBS (p>0.05). But the axonal type have more respiratory failure cases than the demyelinating type (p<0.05).(2) In the eletrophysiological testing, the abnormality frequency of DML, MCV, SCV, F-wave were higher in demyelinating GBS than those in axonal GBS (p<0.05), while there was no difference of CMAP amplitude in midean, ulnar and tibial nerves between them (p>0.05). In demyelinating GBS, the abnormality frequency of CMAP amplitude in peroneal nerves was lower than that in axonal GBS, while the abnormality frequency of SNAP amplitude in sural nerves was lower than that in midean nerve or ulnar nerve (p<0.05).(3) There was no difference of Hughes score in nadir, 1 month after onset between two types. However, the Hughes grading of the demyelinating type after 3 and 6 months was better than of the axonal type.Conclutions:(1) There is no difference of the age on onset, presymptoms, time to peak, muscular force score and grade of sensory abnormality in nadir, cranial nerve impairment and ratio of several cases between the demyelinating and axonal GBS, but respiratory muscle involvement is more often in the axonal GBS that in demyelinating GBS.(2) The amplitude of CMAP could not be the difference hallmark between axomal GBS and demyelinating GBS. The peroneal were more easily to be involved in axonal GBS than that in demyelinating type;The sural nerves were less damaged than other nerves in demyelinating GBS.(3) The prognosis of demyelinating GBS is better than that of axonal type in 3 and 6 months after onset.